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Acta Ortopedica Mexicana 2010
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Acta Ortopedica Mexicana 2010
Review
Topics: Chemical Phenomena; History, 20th Century; Mechanical Phenomena; Osteolysis; Polyethylene; Product Packaging; Sterilization; Vitamin E
PubMed: 20836377
DOI: No ID Found -
Molecules (Basel, Switzerland) Mar 2019Velcrands are a specific class of cavitands whose complementary surfaces induce self-dimerization. The insertion of a velcrand as physical cross-linking unit into a...
Velcrands are a specific class of cavitands whose complementary surfaces induce self-dimerization. The insertion of a velcrand as physical cross-linking unit into a polymer is reported. To this purpose, the velcrand was functionalized at the lower rim with an isocyanate group. The functional velcrand was reacted with poly (ethylene-co-(2-hydroxethylmethacrylate)) (PE-HEMA), a polymer equipped with free hydroxyl groups suitable for reaction with the isocyanate group. The obtained functionalized polymer was characterized by nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR), proving the introduction of velcraplexes in the polymer. Films with varying amounts of velcrands were obtained by solution casting and slow evaporation, testifying the processability of the functionalized polymers. The obtained films were used to measure the oxygen barrier properties of the functionalized material.
Topics: Calorimetry, Differential Scanning; Chemistry Techniques, Synthetic; Magnetic Resonance Spectroscopy; Oxygen; Polyethylene; Spectroscopy, Fourier Transform Infrared
PubMed: 30841484
DOI: 10.3390/molecules24050902 -
Environmental Science & Technology May 2011Plastic waste disposal is one of the serious environmental issues being tackled by our society today. Polyethylene, particularly in packaging films, has received... (Review)
Review
Plastic waste disposal is one of the serious environmental issues being tackled by our society today. Polyethylene, particularly in packaging films, has received criticism as it tends to accumulate over a period of time, leaving behind an undesirable visual footprint. Degradable polyethylene, which would enter the eco-cycle harmlessly through biodegradation would be a desirable solution to this problem. However, the "degradable polyethylene" which is presently being promoted as an environmentally friendly alternative to the nondegradable counterpart, does not seem to meet this criterion. This article reviews the state of the art on the aspect of degradability of polyethylene containing pro-oxidants, and more importantly the effect these polymers could have on the environment in the long run. On exposure to heat, light, and oxygen, these polymers disintegrate into small fragments, thereby reducing or increasing the visual presence. However, these fragments can remain in the environment for prolonged time periods. This article also outlines important questions, particularly in terms of time scale of complete degradation, environmental fate of the polymer residues, and possible accumulation of toxins, the answers to which need to be established prior to accepting these polymers as environmentally benign alternatives to their nondegradable equivalents. It appears from the existing literature that our search for biodegradable polyethylene has not yet been realized.
Topics: Biodegradation, Environmental; Environmental Pollutants; Green Chemistry Technology; Polyethylene; Reactive Oxygen Species
PubMed: 21495645
DOI: 10.1021/es104042f -
Chemosphere Aug 2006Prooxidant additives represent a promising solution to the problem of the environment contamination with polyethylene film litter. Prooxidants accelerate photo- and... (Review)
Review
Prooxidant additives represent a promising solution to the problem of the environment contamination with polyethylene film litter. Prooxidants accelerate photo- and thermo-oxidation and consequent polymer chain cleavage rendering the product apparently more susceptible to biodegradation. The question not fully resolved remains the biodegradation itself, its mechanism and especially the factors influencing the time-frame in which it can occur. The presented review is aimed to provide comprehensible information for both microbiologists and polymer scientists, who need participate in the research leading to an understanding of the microorganism action on the oxidized polyethylene and to design of new materials.
Topics: Biodegradation, Environmental; Environmental Pollutants; Oxidants; Polyethylene; Refuse Disposal
PubMed: 16487569
DOI: 10.1016/j.chemosphere.2005.12.060 -
Seminars in Immunopathology May 2011This paper first presents a brief overview about the mechanism of wear particle formation as well as wear particle characteristics in metal-on-polyethylene and... (Review)
Review
This paper first presents a brief overview about the mechanism of wear particle formation as well as wear particle characteristics in metal-on-polyethylene and metal-on-metal artificial hip joints. The biological effects of such particles are then described, focusing on the inflammatory response induced by each type of particles as well as on how metal wear products may be the source of a T lymphocyte-mediated specific immune response, early adverse tissue responses, and genotoxicity. Finally, some of the current in vivo models used for the analysis of tissue response to various wear particles are presented.
Topics: Animals; Humans; Inflammation; Metals; Models, Animal; Polyethylene; Prostheses and Implants; Prosthesis Failure
PubMed: 21267569
DOI: 10.1007/s00281-011-0242-3 -
The Knee Jun 2004Over the last 10 years there has been increasing concern over wear of polyethylene and osteolytic potential in the knee. During this period there have been considerable... (Review)
Review
Over the last 10 years there has been increasing concern over wear of polyethylene and osteolytic potential in the knee. During this period there have been considerable developments in both the design, materials and sterilisation techniques used for polyethylene in the knee. This paper reviews wear performance of polyethylene sterilised by different techniques, under a range of kinematics conditions in a single knee joint simulator system. Reducations in polyethylene wear were found with both stabilised polyethylene and cross-linked polyethylene, and with rotating platform mobile bearing designs.
Topics: Biomechanical Phenomena; Gamma Rays; Humans; Knee Prosthesis; Polyethylene; Polyethylenes; Prosthesis Failure; Sterilization
PubMed: 15194091
DOI: 10.1016/j.knee.2003.10.002 -
Plastic and Reconstructive Surgery... Feb 1951
Topics: Humans; Polyethylene; Polyethylenes
PubMed: 14816052
DOI: 10.1097/00006534-195102000-00006 -
Environmental Microbiology Jun 2024Plastic pollution is a vast and increasing problem that has permeated the environment, affecting all aspects of the global food web. Plastics and microplastics have...
Plastic pollution is a vast and increasing problem that has permeated the environment, affecting all aspects of the global food web. Plastics and microplastics have spread to soil, water bodies, and even the atmosphere due to decades of use in a wide range of applications. Plastics include a variety of materials with different properties and chemical characteristics, with polyethylene being a dominant fraction. Polyethylene is also an extremely persistent compound with slow rates of photodegradation or biodegradation. In this study, we developed a method to isolate communities of microbes capable of biodegrading a polyethylene surrogate. This method allows us to study potential polyethylene degradation over much shorter time periods. Using this method, we enriched several communities of microbes that can degrade the polyethylene surrogate within weeks. We also identified specific bacterial strains with a higher propensity to degrade compounds similar to polyethylene. We provide a description of the method, the variability and efficacy of four different communities, and key strains from these communities. This method should serve as a straightforward and adaptable tool for studying polyethylene biodegradation.
Topics: Polyethylene; Biodegradation, Environmental; Bacteria; Microbiota; Soil Microbiology
PubMed: 38843592
DOI: 10.1111/1462-2920.16658 -
Revista Espanola de Cirugia Ortopedica... 2018To compare two different types of inserts: Ultra-high molecular weight polyethylene (UHMWPE) and cross-linked polyethylene with a quantitative and qualitative study of... (Comparative Study)
Comparative Study Randomized Controlled Trial
AIM
To compare two different types of inserts: Ultra-high molecular weight polyethylene (UHMWPE) and cross-linked polyethylene with a quantitative and qualitative study of polyethylene wear particles in synovial fluid 3 years after total knee arthroplasty.
MATERIAL AND METHODS
A prospective, randomized, controlled cohort study with blinded evaluation was carried out on 25 patients undergoing staged bilateral total knee replacement, 6 months apart. Knee arthrocentesis was performed on 12 patients 3 years after surgery, and the polyethylene particles were analyzed.
RESULTS
No significant differences were found in the number of particles generated by the two different types of inserts at 3 years from total knee arthroplasty (3,000×: x¯ cross-linked=849.7; x¯ UHMWPE=796.9; P=.63; 20,000×: x¯ cross-linked=66.3; x¯ UHMWPE=73.1; P=.76). Likewise, no differences in the probability of finding elongated (χ=0.19; P=.66) or rounded (χ=1.44; P=.23) particles in both types of inserts were observed. However, the probability of finding fibrillar particles is 3.08 times greater in UHMWPE.
CONCLUSIONS
Cross-linked polyethylene does not significantly reduce the generation of polyethylene particles in patients with total knee arthroplasty, 3 years after the surgical procedure.
Topics: Aged; Aged, 80 and over; Arthroplasty, Replacement, Knee; Female; Follow-Up Studies; Humans; Knee Prosthesis; Male; Outcome Assessment, Health Care; Polyethylene; Polyethylenes; Prospective Studies; Prosthesis Failure; Single-Blind Method; Synovial Fluid
PubMed: 29454601
DOI: 10.1016/j.recot.2017.11.004